Reloading and velocity questions Do my numbers look right?

[RedDogFabrication]

So I recently started reloading for my 308 bolt gun and I worked up some rounds the other day. My velocities seem on the high side by 100 fps and wanted a second opinion So I ran four of each through the chrono and this is what I got. I also ran my .22 through it and got 1200 fps which is right where I was expecting. This could just be me being paranoid. The primers all look good non flattened the Accuracy was outstanding no sticky bolt so signs of over pressure at all. I am well within the range for Varget / 175 SMK. The barrel is 24" with a 2" brake I was expecting 2650-2700 but was quite supprised when I was hitting in the 2800 range. My chrono was 10 feet away ammo temp was 60 degrees verified with an infrared thermometer. So am I over thinking this or am I getting false readings. If they were false I would not expect them to be as consistent as they are and climb predictably with the increase in powder.

Here are my results
28001

[20X11]

You were expecting less based on what? a reloading manual? did they happen to tell you the barrel length they used for testing? Readings look right to me.

[RedDogFabrication]

Just based on Internet chatter my book did not have a 175 grain section. I was looking for other people running Varget / 175 SMK's and that seemed like the 2650 was territory they were in so I expected a bit less dont know what barrel lengths were. not complaining It shoots great and I like stated above pressure appears to be in check. Just checking really I am new to the reloading game. This is the best group I had with the 43.5 grain loads

28005

[hghclsswhitetrsh]

This is from my Sierra book. I don't mow if this will help but here ya go... It shows 41.7 max load for varget.

http://i1036.photobucket.com/albums/a441/RamboZuki84/D69E9DBD-8C04-4F11-AFE9-B8F1B5FBC02B-1406-000000ABEB2B61C3_zps1e68e924.jpg

[DHC]

So I recently started reloading for my 308 bolt gun and I worked up some rounds the other day. My velocities seem on the high side by 100 fps and wanted a second opinion So I ran four of each through the chrono and this is what I got. I also ran my .22 through it and got 1200 fps which is right where I was expecting. This could just be me being paranoid. The primers all look good non flattened the Accuracy was outstanding no sticky bolt so signs of over pressure at all. I am well within the range for Varget / 175 SMK. The barrel is 24" with a 2" brake I was expecting 2650-2700 but was quite supprised when I was hitting in the 2800 range. My chrono was 10 feet away ammo temp was 60 degrees verified with an infrared thermometer. So am I over thinking this or am I getting false readings. If they were false I would not expect them to be as consistent as they are and climb predictably with the increase in powder.

Here are my results
28001


I'll post up results from the QuickLoad simulation using your specs - see attached screen capture. My chrono readings seemed pretty close to the QL simulations, but I was using different powders than you are.

IHTH

28013

[20X11]

Which begs the question...what oal did you load to?

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2

[RedDogFabrication]

So my original velocity predictions were close to your Simulator, my chrono is off? I am at 10 feet I will try pushing back to 15 and see if it makes a difference. Or my scale is off by a lot and I am hot loading my rounds. I have heard that 45 grains starts to become a compressed load and I dont think I am compressing yet so going to assume scale is good.

28015 28017 Primers are in order 43, 43.5, 44

[RedDogFabrication]

2.804 puts me .002 off the rifling so thats what I am loaded to

[RedDogFabrication]

The more I read the more I think my chrono is off I dont think it is possible to get the numbers I have with the combination I have. I Hit a 36 inch tall target at 807 with 5.7 mils of hold this put me lower third of the target. I had 2715 plugged into my calculator to get to that number and it was not off by much. "not really sure why I had that number" If 2800 were accurate I would expect to see massive pressure signs or failure. I think I will just need to get out to the range and try it again. I dont think I will change the load but open to suggestions.

[C Ward]

Who's chrono, there are more than one that is famous for being wrong . Light conditions on the skyscreens can create variation as well .

Ammo temp is pretty well a non issue with Varget , I've chrono'd my 308 load from about 15F to 100 F and the velocity swing was maybe 20 FPS .

Settle on one brand of brass , mixed brass will create all kinds of issues because of case capacity differences .

My load was 44-44.5 in a Win case and a BR2 primer and it would constantly run 2730 out of a 26" Krieger .

Who's barrel is it , my new Bartlien is pushing M118LR at 2760 at 26" which is fast for that ammo but its been my experience their barrels run fast .

[Rucker61]

I'm running 44 gr Varget, Winchester brass, CCI large rifle primers and Barnes 168 gr TTSX, 22" Tikka T3 Lite. Average MV is 2700 fps.

[SA Friday]

I think your chrono is running a bit off for this batch of testing, but as previously mentioned, lighting is probably more of a problem than the machine being miscalculated. I run two different 308's, a Rem 700 PSS factory 26" barrel and a custom rifle with a 26" Kreiger barrel and they both are running 175's at 2730 fps. This is a 44.0-44.2 gr load of Varget depending on the brass.

I would recommend running 5 round groups to determine accuracy. 3 round groups can lie to you.

This thread might help in your future tests. http://www.ar-15.co/threads/30291-How-I-work-up-a-new-reload/page2?highlight=reload

[smchop]

I would test it at distance and see what your come ups are. That will help you get real info on what the load is doing. See what your MOA or MIL dial ups are out to 600 or more and compare that to ballistics and see where your at.

[DHC]

Who's chrono, there are more than one that is famous for being wrong . Light conditions on the skyscreens can create variation as well .

Ammo temp is pretty well a non issue with Varget , I've chrono'd my 308 load from about 15F to 100 F and the velocity swing was maybe 20 FPS .

Settle on one brand of brass , mixed brass will create all kinds of issues because of case capacity differences .

My load was 44-44.5 in a Win case and a BR2 primer and it would constantly run 2730 out of a 26" Krieger .

Who's barrel is it , my new Bartlien is pushing M118LR at 2760 at 26" which is fast for that ammo but its been my experience their barrels run fast .

As a point of reference, I'll attach a few chrono results w/accompanying targets.

Rifle:
* Bighorn Arms .308
* Chanlynn 25" barrel 1:11 twist

Chrono: Competition Electronics ProChrono Digital w/Remote - tripod at approximately 12' from muzzle - diffusers used

Date/Location: April 28, 2013 at Golden Gun Club - 58 degrees and sunny w/light winds about 10mph

Here is a 10-shot group with Lake City M118LR (175 SMK's). Point of Aim was the top point of the diamond (per islandermyk: "Aim small - miss small."). The 10 shots in the string are all touching - the 3 shots not touching were from another string of shots. Lo: 2726 Hi: 2754 Avg: 2738 ES: 28 SD: 10

28075


Next up is a 9-shot group with FGMM 175gr SMK's. Point of aim was bottom point on the diamond. The 9 shots in the string are again all touching, though clustered in 2 groups horizontally. The other shots are from a different string. Lo: 2645 Hi: 2693 Avg: 2675 ES: 48 SD: 17

28079

Next up is a 10-shot string with some handloads using these components: Hornady match cases, Fed 210M primers, Sierra 175gr SMK's and 42.0 gr of IMR4895. Lo: 2666 Hi: 2715 Avg: 2693 ES: 49 SD: 16

28085

The rifle is capable of shooting far FAR better than these targets would indicate, but the chrono results should be useful as a reference. Unfortunately, I did not have any Varget at the time and have not yet chrono'd any results with Varget. Still trying to 'settle in' on brass and powder combo.

IHTH

[RedDogFabrication]

So consensus is my chrono was reading off, pressures are probably under max, make some more at 43.5gr and test again?

[C Ward]

If the chrono numbers are to good to be true they usually are . The only way to know for sure is to go out and get real world data and back calculate the MV .

Pretty much every 308 that I have run across will shoot with 44 - 44.5 grs of Varget , BR2 or Fed 210M primer , and 175 Match King .

The Hodgdon extreme line powders are my go to powder for precision rifle ammo , they are the most temp stable stuff out there and takes that issue out of the equation .

Winchester , LC , or Lapua is the only brass that is hard enough to give good case life . The rest is soft enough that case life is half or less of these .

Federal match ammo is known for being loaded conservatively so those numbers don't surprise me . On my precision rifle ammo I keep my SD's at 10 and under and the ES's 25 and under .

The Chanlynn barrels that I have run across have run on the fast side .